Compare "argparse", in Python.[1] There are a number of argument parsers like this. They have some way to describe the expected form of the command line, and check it. Errors result in a "usage" message which shows the desired form of the command line in the usual "help" style.<p>Github has at least three C++ implementations of "argparse". Here's a header-only one.[2]<p>[1] <a href="https://docs.python.org/3/library/argparse.html" rel="nofollow">https://docs.python.org/3/library/argparse.html</a>
[2] <a href="https://github.com/hbristow/argparse" rel="nofollow">https://github.com/hbristow/argparse</a>